Hector, what happens if you pull one out? Fungus does look like mushrooms and you can see the gills underneath. Wasp nests are made out of a 'papery' substance and very different when you touch them.
Wasp nests look a little similar but are not attached to the soil. They would be attached above ground where there is shelter. For example in the shed on the ceiling or high up on the walls. Earth wasps come out of a hole in the ground and don't make such wasp nests.